Reportr.net has a piece on how quickly wrong information was spread in the mainstream media from and through Twitter, using the events in Tucson as an example. I found this part interesting:

Journalism can be a messy process. This process used to take place behind close doors in newsrooms, as reporters and editors considered conflicting reports, weighed up incoming information and made decisions on what to publish.

Today, the process of journalism is taking place in public on media platforms such as Twitter. Information is published, disseminated, checked, confirmed or denied in public through a pro-am collaboration facilitated by social networks.

Instead of editors fact checking before publishing, mainstream news is depending on the public to do this. Remember this the next time someone tries to make the point that corporate journalism has a fact-checking filter that citizen journalism doesn’t. One could blame it on the rapid news cycles brought on by technology. Personally, I think that practices that were traditionally kept from public view on how the news is processed are finally surfacing. Corporate newsrooms are full of reporters and editors who are just as lost as the rest of us. One difference that may factor in this, especially in TV news, is that station managers tend to be promoted from the sales departments. So the big bosses in local TV news don’t have journalism backgrounds but come from an environment of selling air. This attitude of making money out of something abstract can affect the mood of the station–push out product to sell more air.

The public forgets their mistakes. In fact, the public is doing their jobs for them.